Nucleobase Concentrations from Murchison Meteorite and Soil Samples in Parts per Billion

Question

Nucleobase Murchison meteorite sample 1 Murchison meteorite sample 2 Murchison soil sample
Isoguanine


not detected
Purine


not detected
Xanthine



Adenine



Hypoxanthine



Employing high-performance liquid chromatography—a process that uses pressurized water to separate material into its component molecules—astrochemist Yashiro Oba and colleagues analyzed two samples of the Murchison meteorite that landed in Australia as well as soil from the landing zone of the meteorite to determine the concentrations of various organic molecules. By comparing the relative concentrations of types of molecules known as nucleobases in the Murchison meteorite with those in the soil, the team concluded that there is evidence that the nucleobases in the Murchison meteorite formed in space and are not the result of contamination on Earth.
Which choice best describes data from the table that support the team’s conclusion?
Choose 1 answer:
Choose 1 answer:
(Choice A) Adenine and xanthine were detected in both of the meteorite samples and in the soil sample.
A
Adenine and xanthine were detected in both of the meteorite samples and in the soil sample.
(Choice B) Isoguanine and hypoxanthine were detected in the Murchison meteorite sample 1 but not in sample 2.
B
Isoguanine and hypoxanthine were detected in the Murchison meteorite sample 1 but not in sample 2.
(Choice C) Isoguanine and purine were detected in both meteorite samples but not in the soil sample.
C
Isoguanine and purine were detected in both meteorite samples but not in the soil sample.
(Choice D) Hypoxanthine and purine were detected in both the Murchison meteorite sample 2 and in the soil sample.
D
Hypoxanthine and purine were detected in both the Murchison meteorite sample 2 and in the soil sample.

Answer 1

The correct choice is:

(Choice C) Isoguanine and purine were detected in both meteorite samples but not in the soil sample.

This supports the team's conclusion that the nucleobases in the Murchison meteorite are not the result of contamination on Earth, as these specific nucleobases were found in both meteorite samples but not in the soil sample, suggesting a unique composition originating from space.